My.Computer.Mouse.WheelScrollLines Property

Gets a number that indicates how much to scroll when the mouse wheel is rotated one notch.

' Usage
Dim value As Integer = My.Computer.Mouse.WheelScrollLines
' Declaration
Public ReadOnly Property WheelScrollLines As Integer

An Integer that indicates how much to scroll when the mouse wheel is rotated one notch. A positive value indicates scrolling by that number of lines, while a negative value indicates scrolling by one screen at a time.

The following conditions can cause an exception:

• The computer has no mouse installed (InvalidOperationException).

• The mouse has no scroll wheel (InvalidOperationException).

You can use this property to determine how many lines to scroll up or down in a multi-line control that has a scroll bar.

The My.Computer.Mouse.WheelScrollLines property provides functionality similar to the MouseWheelScrollLines property.

Because this property throws an exception if the mouse does not have a scroll wheel, you should make sure a mouse has a scroll wheel by checking the My.Computer.Mouse.WheelExists property.

This property provides information about the computer that runs the code.

This example determines if the mouse has a scroll wheel and uses the My.Computer.Mouse.WheelExists property to determine how much to scroll when the mouse wheel is rotated.

If My.Computer.Mouse.WheelExists Then 
    Dim lines As Integer = My.Computer.Mouse.WheelScrollLines
    If lines > 0 Then
        MsgBox("Application scrolls " & _
            lines & " line(s) for each wheel turn.")
    Else
        MsgBox("Application scrolls " & _
            (-lines) & " page(s) for each wheel turn.")
    End If 
Else
    MsgBox("Mouse has no scroll wheel.")
End If

Namespace:Microsoft.VisualBasic.Devices

Class:Mouse

Assembly: Visual Basic Runtime Library (in Microsoft.VisualBasic.dll)

No permissions are required.

My.Computer.Mouse Object

My.Computer.Mouse.WheelExists Property

Mouse.WheelScrollLines